Henri Cramer's '4 Piéces differentes' Op. 43 are likely pedagogical works from the Classical or early Romantic era, designed to develop specific pianistic skills. They would typically feature clear textures and structured forms.
Developing clean articulation and evenness of touch, especially in rapid passages, is a primary technical goal.
4 Piéces differentes (Op.43) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of 4 Piéces differentes (Op.43) lasts about 7 minutes.
4 Piéces differentes (Op.43) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.